Primer Insert Having a Primer Pocket Groove

ABSTRACT

The present invention provides a primer insert for use in a polymeric ammunition cartridge includes a top surface opposite a bottom surface and a extraction flange that extends circumferentially about an outer edge of the top surface; a coupling element that extends from the bottom surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; a primer recess in the top surface that extends toward the bottom surface, wherein the primer recess comprises a recess bottom and a circular recess side wall; a primer flash aperture through the recess bottom that extends through the bottom surface, wherein the primer flash aperture is adapted to receive a polymer overmolding to form a flash hole; and a groove in the primer recess positioned around the primer flash aperture adapted to receive a polymer overmolding, wherein the groove extends at least partially over the bottom surface and the circular recess side wall and the groove is adapted to receive polymer through the primer flash aperture and over the bottom surface and the circular recess side wall.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of co-pending U.S. patentapplication Ser. No. 15/406,844 filed on Jan. 16, 2017, which is acontinuation application of U.S. patent application Ser. No. 14/011,202filed on Aug. 27, 2013 now U.S. Pat. No. 9,546,849, which is a divisionof U.S. patent application Ser. No. 13/292,843 filed on Nov. 9, 2011 nowU.S. Pat. No. 8,561,543 issued Oct. 13, 2013, which claims the benefitof U.S. Provisional Patent Application Ser. No. 61/456,664, filed Nov.10, 2010, the contents of each are hereby incorporated by reference intheir entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention relates in general to the field of ammunition,specifically to compositions of matter and methods of making and usingpolymeric ammunition, cartridges, and primer inserts.

STATEMENT OF FEDERALLY FUNDED RESEARCH

None.

INCORPORATION-BY-REFERENCE OF MATERIALS FILED ON COMPACT DISC

None.

BACKGROUND OF THE INVENTION

Without limiting the scope of the invention, its background is describedin connection with lightweight polymer cartridge casing ammunition.Conventional ammunition cartridge casings for rifles and machine guns,as well as larger caliber weapons, are made from brass, which is heavy,expensive, and potentially hazardous. There exists a need for anaffordable lighter weight replacement for brass ammunition cartridgecases that can increase mission performance and operationalcapabilities. Lightweight polymer cartridge casing ammunition must meetthe reliability and performance standards of existing fielded ammunitionand be interchangeable with brass cartridge casing ammunition inexisting weaponry. Reliable cartridge casings manufacture requiresuniformity (e.g., bullet seating, bullet-to-casing fit, casing strength,etc.) from one cartridge to the next in order to obtain consistentpressures within the casing during firing prior to bullet and casingseparation to create uniformed ballistic performance. Plastic cartridgecasings have been known for many years but have failed to providesatisfactory ammunition that could be produced in commercial quantitieswith sufficient safety, ballistic, handling characteristics, and survivephysical and natural conditions to which it will be exposed during theammunition's intended life cycle; however, these characteristics havenot been achieved.

For example, U.S. patent application Ser. No. 11/160,682 discloses abase for a cartridge casing body for an ammunition article, the basehaving an ignition device; an attachment device at one end thereof, theattachment device being adapted to the base to a cartridge casing body;wherein the base is made from plastic, ceramic, or a composite material.

U.S. Pat. No. 7,610,858 discloses an ammunition cartridge assembled froma substantially cylindrical polymeric cartridge casing body defining acasing headspace with an open projectile-end and an end opposing theprojectile-end, wherein the casing body has a substantially cylindricalinjection molded polymeric bullet-end component with opposing first andsecond ends, the first end of which is the projectile-end of the casingbody and the second end has a male or female coupling element; and acylindrical polymeric middle body component with opposing first andsecond ends, wherein the first end has a coupling element that is a matefor the projectile-end coupling element and joins the first end of themiddle body component to the second end of the bullet-end component, andthe second end is the end of the casing body opposite the projectile endand has a male or female coupling element; and a cylindrical cartridgecasing head-end component with an essentially closed base end with aprimer hole opposite an open end with a coupling element that is a matefor the coupling element on the second end of the middle body and joinsthe second end of the middle body component to the open end of thehead-end component; wherein the middle body component is formed from amaterial more ductile than the material head-end component is formedfrom but equal or less ductile than the material the bullet-endcomponent is formed from. Methods for assembling ammunition cartridgesand ammunition cartridges having the headspace length larger than thecorresponding headspace length of the chamber of the intended weaponmeasured at the same basic diameter for the cartridge casing withoutbeing so large as to jam the weapon or otherwise interfere with itsaction are also disclosed.

Shortcomings of the known methods of producing plastic or substantiallyplastic ammunition include the possibility of the projectile beingpushed into the cartridge casing, the bullet pull being too light suchthat the bullet can fall out, the bullet pull being too insufficient tocreate sufficient chamber pressure, the bullet pull not being uniformfrom round to round, and portions of the cartridge casing breaking offupon firing causing the weapon to jam or damage or danger whensubsequent rounds are fired or when the casing portions themselvesbecome projectiles. To overcome the above shortcomings, improvements incartridge case design and performance polymer materials are needed.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a primer insert for use in a polymericammunition cartridge includes a top surface opposite a bottom surfaceand a extraction flange that extends circumferentially about an outeredge of the top surface; a coupling element that extends from the bottomsurface, wherein the substantially cylindrical coupling element isadapted to receive a polymer overmolding; a primer recess in the topsurface that extends toward the bottom surface, wherein the primerrecess comprises a recess bottom and a circular recess side wall; aprimer flash aperture through the recess bottom that extends through thebottom surface, wherein the primer flash aperture is adapted to receivea polymer overmolding to form a flash hole; and a groove in the primerrecess positioned around the primer flash aperture adapted to receive apolymer overmolding, wherein the groove extends at least partially overthe bottom surface and the circular recess side wall and the groove isadapted to receive polymer through the primer flash aperture and overthe bottom surface and the circular recess side wall.

In one embodiment, the groove extends up the circular recess side wallabout 95-100 percent the distance from the recess bottom to the topsurface. In another embodiment, the groove extends up the circularrecess side wall about 95 percent the distance from the recess bottom tothe top surface. In another embodiment, the groove extends up thecircular recess side wall about 96 percent the distance from the recessbottom to the top surface. In another embodiment, the groove extends upthe circular recess side wall about 97 percent the distance from therecess bottom to the top surface. In another embodiment, the grooveextends up the circular recess side wall about 98 percent the distancefrom the recess bottom to the top surface. In another embodiment, thegroove extends up the circular recess side wall about 99 percent thedistance from the recess bottom to the top surface. In anotherembodiment, the groove extends to about 100 percent of the circularrecess side wall. The coupling element comprises an inner surfaceadapted to receive a polymer overmolding and an outer surface adapted toreceive a polymer overmolding. The primer insert includes an outermolding groove that extends circumferentially about an outer edge of thetop surface. The primer insert has a caliber selected from .223, .243,.25-06, .270, .300, .308, .338, .30-30, .30-06, .45-70 or 0.50-90, 50caliber, 45 caliber, 380 caliber or 38 caliber, 5.56 mm, 6 mm, 7 mm,7.62 mm, 8 mm, 9 mm, 10 mm, or 12.7 mm. The primer insert is a 5.56 mm,7.62 mm, .223, 308, 338, 12.7 mm, and .50 caliber primer insert. Theprimer insert comprises a metal, an alloy, a polymer or a ceramic alloy.The primer insert comprises steel, nickel, chromium, copper, carbon,iron, stainless steel or brass. The primer insert comprises a 102, 174,201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408,409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or 601-665 gradestainless steel. The primer insert comprises a Ti₆Al₄V. The primerinsert comprises a groove texture.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

For a more complete understanding of the features and advantages of thepresent invention, reference is now made to the detailed description ofthe invention along with the accompanying figures and in which:

FIG. 1 depicts a side, cross-sectional view of a polymeric cartridgecase according to one embodiment of the present invention;

FIG. 2 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 3 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 4 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 5 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 6 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 7 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 8 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention;

FIG. 9 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case displaying ribs according to one embodiment ofthe present invention;

FIG. 10 depicts a side, cross-sectional view of a polymeric cartridgecase having a diffuser according to one embodiment of the presentinvention;

FIG. 11 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case having a diffuser according to one embodimentof the present invention;

FIGS. 12-13 show a bottom view of the polymer casing; and

FIG. 14 depicts an elevated, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the presentinvention are discussed in detail below, it should be appreciated thatthe present invention provides many applicable inventive concepts thatcan be embodied in a wide variety of specific contexts. The specificembodiments discussed herein are merely illustrative of specific ways tomake and use the invention and do not delimit the scope of theinvention.

To facilitate the understanding of this invention, a number of terms aredefined below. Terms defined herein have meanings as commonly understoodby a person of ordinary skill in the areas relevant to the presentinvention. Terms such as “a”, “an” and “the” are not intended to referto only a singular entity, but include the general class of which aspecific example may be used for illustration. The terminology herein isused to describe specific embodiments of the invention, but their usagedoes not delimit the invention, except as outlined in the claims.

Reliable cartridge manufacture requires uniformity from one cartridge tothe next in order to obtain consistent ballistic performance. Amongother considerations, proper bullet seating and bullet-to-casing fit isrequired. In this manner, a desired pressure develops within the casingduring firing prior to bullet and casing separation. Historically,bullets employ a cannelure, which is a slight annular depression formedin a surface of the bullet at a location determined to be the optimalseating depth for the bullet. In this manner, a visual inspection of acartridge could determine whether or not the bullet is seated at theproper depth. Once the bullet is inserted into the casing to the properdepth, one of two standard procedures is incorporated to lock the bulletin its proper location. One method is the crimping of the entire end ofthe casing into the cannelure. A second method does not crimp the casingend; rather the bullet is pressure fitted into the casing.

The polymeric ammunition cartridges of the present invention are of acaliber typically carried by soldiers in combat for use in their combatweapons. The present invention is not limited to the described caliberand is believed to be applicable to other calibers as well. Thisincludes various small and medium caliber munitions, including 5.56 mm,7.62 mm and .50 caliber ammunition cartridges, as well as medium/smallcaliber ammunition such as 380 caliber, 38 caliber, 9 mm, 10 mm, 20 mm,25 mm, 30 mm, 40 mm, 45 caliber and the like. The cartridges, therefore,are of a caliber between about 0.05 and about 5 inches. Thus, thepresent invention is also applicable to the sporting goods industry foruse by hunters and target shooters.

FIG. 1 depicts a side, cross-sectional view of a polymeric cartridgecase according to one embodiment of the present invention. A cartridge10 suitable for use with high velocity rifles is shown manufactured witha polymer casing 12 showing a powder chamber 14 with projectile (notshown) inserted into the forward end opening 16. Polymer casing 12 has asubstantially cylindrical open-ended polymeric bullet-end 18 extendingfrom forward end opening 16 rearward to opposite end 20. The bullet-endcomponent 18 may be formed with coupling end 22 formed on end 20.Coupling end 22 is shown as a female element, but may also be configuredas a male element in alternate embodiments of the invention. The forwardend of bullet-end component 18 has a shoulder 24 forming chamber neck26. The bullet-end component typically has a wall thickness betweenabout 0.003 and about 0.200 inches and more preferably between about0.005 and more preferably between about 0.150 inches about 0.010 andabout 0.050 inches.

The middle body component 28 is connected to a substantially cylindricalcoupling element 30 of the substantially cylindrical insert 32. Couplingelement 30, as shown may be configured as a male element, however, allcombinations of male and female configurations is acceptable forcoupling elements 30 and coupling end 22 in alternate embodiments of theinvention. Coupling end 22 of bullet-end component 18 fits about andengages coupling element 30 of a substantially cylindrical insert 32.The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A primer flash hole40 is located in the primer flash hole 40 and extends through the bottomsurface 34 into the powder chamber 14. The coupling end 22 extends thepolymer through the primer flash hole 40 to form an aperture coating 42while retaining a passage from the top surface 36 through the bottomsurface 34 and into the powder chamber 14 to provide support andprotection about the primer flash hole 40. When contacted the couplingend 22 interlocks with the substantially cylindrical coupling element30, through the coupling element 30 that extends with a taper to asmaller diameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28. The middle body component extends from a forward endopening 16 to coupling element 22. The middle body component typicallyhas a wall thickness between about 0.003 and about 0.200 inches and morepreferably between about 0.005 and more preferably between about 0.150inches about 0.010 and about 0.050 inches.

The bullet-end 16, middle body 18 and bottom surface 34 define theinterior of powder chamber 14 in which the powder charge (not shown) iscontained. The interior volume of powder chamber 14 may be varied toprovide the volume necessary for complete filling of the chamber 14 bythe propellant chosen so that a simplified volumetric measure ofpropellant can be utilized when loading the cartridge. Either aparticulate or consolidated propellant can be used.

The substantially cylindrical insert 32 also has a flange 46 cut thereinand a primer recess 38 formed therein for ease of insertion of theprimer (not shown). The primer recess 38 is sized so as to receive theprimer (not shown) in an interference fit during assembly. A primerflash hole 40 communicates through the bottom surface 34 ofsubstantially cylindrical insert 32 into the powder chamber 14 so thatupon detonation of primer (not shown) the powder in powder chamber 14will be ignited.

Projectile (not shown) is held in place within chamber case neck 26 atforward opening 16 by an interference fit. Mechanical crimping of theforward opening 16 can also be applied to increase the bullet pullforce. The bullet (not shown) may be inserted into place following thecompletion of the filling of powder chamber 14. Projectile (not shown)can also be injection molded directly onto the forward opening 16 priorto welding or bonding together using solvent, adhesive, spin-welding,vibration-welding, ultrasonic-welding or laser-welding techniques. Thewelding or bonding increases the joint strength so the casing can beextracted from the hot gun casing after firing at the cook-offtemperature.

The bullet-end and bullet components can then be welded or bondedtogether using solvent, adhesive, spin-welding, vibration-welding,ultrasonic-welding or laser-welding techniques. The welding or bondingincreases the joint strength so the casing can be extracted from the hotgun casing after firing at the cook-off temperature. An optional firstand second annular grooves (cannelures) may be provided in thebullet-end in the interlock surface of the male coupling element toprovide a snap-fit between the two components. The cannelures formed ina surface of the bullet at a location determined to be the optimalseating depth for the bullet. Once the bullet is inserted into thecasing to the proper depth to lock the bullet in its proper location.One method is the crimping of the entire end of the casing into thecannelures.

The bullet-end and middle body components can then be welded or bondedtogether using solvent, adhesive, spin-welding, vibration-welding,ultrasonic-welding or laser-welding techniques. The welding or bondingincreases the joint strength so the casing can be extracted from the hotgun casing after firing at the cook-off temperature.

FIG. 2 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends from 5 to 25% of thedistance from the flash hole aperture 41 to the side of the primerrecess 38. The groove 35 may be of any depth in the primer recess 38 andmay extend away from the flash hole aperture 41 toward the wall of theprimer recess 38. In addition, the groove 35 may be textured to furthergrip the overmolding. The texture may be grooves, slots, squares,knurled, hatched, etched or other known surface texturing. The texturemay be of any depth, width or spacing being regular or irregular. Thetexturing may be combinations of textures and/or textured in portions ofthe groove 35. The groove 35 receives the polymer that is overmoldedover the tip 44 and through the flash hole aperture 41 into the groove35. The groove 35 extends away from the flash hole aperture 41 to allowthe overmolding of the polymer into the groove 35 and primer recess 38.The coupling end 22 extends the polymer through the primer flash hole 40to form an aperture coating 42 while retaining a passage from the topsurface 36 through the bottom surface 34 and into the powder chamber 14to provide support and protection about the primer flash hole 40. Whencontacted the coupling end 22 interlocks with the substantiallycylindrical coupling element 30, through the coupling element 30 thatextends with a taper to a smaller diameter at the tip 44 to form aphysical interlock between substantially cylindrical insert 32 andmiddle body component 28. Polymer casing 12 also has a substantiallycylindrical open-ended middle body component 28.

FIG. 3 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends from 26 to 75% of thedistance from the flash hole aperture 41 to the side of the primerrecess 38. The groove 35 may be of any depth in the primer recess 38 andmay extend away from the flash hole aperture 41 toward the wall of theprimer recess 38. In addition, the groove 35 may be textured to furthergrip the overmolding. The texture may be grooves, slots, squares,knurled, hatched, etched or other known surface texturing. The texturemay be of any depth, width or spacing being regular or irregular. Thetexturing may be combinations of textures and/or textured in portions ofthe groove 35. The groove 35 receives the polymer that is overmoldedover the tip 44 and through the flash hole aperture 41 into the groove35. The groove 35 extends away from the flash hole aperture 41 to allowthe overmolding of the polymer into the groove 35 and primer recess 38.The coupling end 22 extends the polymer through the primer flash hole 40to form an aperture coating 42 while retaining a passage from the topsurface 36 through the bottom surface 34 and into the powder chamber 14to provide support and protection about the primer flash hole 40. Whencontacted the coupling end 22 interlocks with the substantiallycylindrical coupling element 30, through the coupling element 30 thatextends with a taper to a smaller diameter at the tip 44 to form aphysical interlock between substantially cylindrical insert 32 andmiddle body component 28. Polymer casing 12 also has a substantiallycylindrical open-ended middle body component 28.

FIG. 4 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends from 75 to 100% of thedistance from the flash hole aperture 41 to the side of the primerrecess 38. The groove 35 may be of any depth in the primer recess 38 andmay extend away from the flash hole aperture 41 toward the wall of theprimer recess 38. In addition, the groove 35 may be textured to furthergrip the overmolding. The texture may be grooves, slots, squares,knurled, hatched, etched or other known surface texturing. The texturemay be of any depth, width or spacing being regular or irregular. Thetexturing may be combinations of textures and/or textured in portions ofthe groove 35. The groove 35 receives the polymer that is overmoldedover the tip 44 and through the flash hole aperture 41 into the groove35. The groove 35 extends away from the flash hole aperture 41 to allowthe overmolding of the polymer into the groove 35 and primer recess 38.The coupling end 22 extends the polymer through the primer flash hole 40to form an aperture coating 42 while retaining a passage from the topsurface 36 through the bottom surface 34 and into the powder chamber 14to provide support and protection about the primer flash hole 40. Whencontacted the coupling end 22 interlocks with the substantiallycylindrical coupling element 30, through the coupling element 30 thatextends with a taper to a smaller diameter at the tip 44 to form aphysical interlock between substantially cylindrical insert 32 andmiddle body component 28. Polymer casing 12 also has a substantiallycylindrical open-ended middle body component 28.

FIG. 5 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends the length of the bottom ofthe primer recess and extends to at least a portion of the sidewall ofthe primer recess. The groove 35 may extend from 2 to 25% of thedistance from the bottom of the primer recess to the top surface 36. Thegroove 35 may be of any depth and may be of equal or varying depth alongits length or may be angled, arced, segmented (positive or negative) orother variations over a portion, segments, or regions of the groove 35.In addition, the groove 35 may be textured to further grip theovermolding. The texture may be grooves, slots, squares, knurled,hatched, etched, indentions, or other known surface texturing. Thetexture may be of any depth, width or spacing being regular orirregular. The texturing may be combinations of textures and/or onlytextured in portions of the groove 35. The groove 35 receives thepolymer that is overmolded over the tip 44 and through the flash holeaperture 41 into the groove 35. The groove 35 extends away from theflash hole aperture 41 to allow the overmolding of the polymer into thegroove 35 and primer recess 38. The coupling end 22 extends the polymerthrough the primer flash hole 40 to form an aperture coating 42 whileretaining a passage from the top surface 36 through the bottom surface34 and into the powder chamber 14 to provide support and protectionabout the primer flash hole 40. When contacted the coupling end 22interlocks with the substantially cylindrical coupling element 30,through the coupling element 30 that extends with a taper to a smallerdiameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28.

FIG. 6 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends the length of the bottom ofthe primer recess and extends to at least a portion of the sidewall ofthe primer recess. The groove 35 may extend from 26 to 75% of thedistance from the bottom of the primer recess to the top surface 36. Thegroove 35 may be of any depth and may be of equal or varying depth alongits length or may be angled, arced, segmented (positive or negative) orother variations over a portion, segments, or regions of the groove 35.In addition, the groove 35 may be textured to further grip theovermolding. The texture may be grooves, slots, squares, knurled,hatched, etched, indentions, or other known surface texturing. Thetexture may be of any depth, width or spacing being regular orirregular. The texturing may be combinations of textures and/or onlytextured in portions of the groove 35. The groove 35 receives thepolymer that is overmolded over the tip 44 and through the flash holeaperture 41 into the groove 35. The groove 35 extends away from theflash hole aperture 41 to allow the overmolding of the polymer into thegroove 35 and primer recess 38. The coupling end 22 extends the polymerthrough the primer flash hole 40 to form an aperture coating 42 whileretaining a passage from the top surface 36 through the bottom surface34 and into the powder chamber 14 to provide support and protectionabout the primer flash hole 40. When contacted the coupling end 22interlocks with the substantially cylindrical coupling element 30,through the coupling element 30 that extends with a taper to a smallerdiameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28.

FIG. 7 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends the length of the bottom ofthe primer recess and extends to at least a portion of the sidewall ofthe primer recess. The groove 35 may extend from 76 to 100% of thedistance from the bottom of the primer recess to the top surface 36. Thegroove 35 may be of any depth and may be of equal or varying depth alongits length or may be angled, arced, segmented (positive or negative) orother variations over a portion, segments, or regions of the groove 35.In addition, the groove 35 may be textured to further grip theovermolding. The texture may be grooves, slots, squares, knurled,hatched, etched, indentions, or other known surface texturing. Thetexture may be of any depth, width or spacing being regular orirregular. The texturing may be combinations of textures and/or onlytextured in portions of the groove 35. The groove 35 receives thepolymer that is overmolded over the tip 44 and through the flash holeaperture 41 into the groove 35. The groove 35 extends away from theflash hole aperture 41 to allow the overmolding of the polymer into thegroove 35 and primer recess 38. The coupling end 22 extends the polymerthrough the primer flash hole 40 to form an aperture coating 42 whileretaining a passage from the top surface 36 through the bottom surface34 and into the powder chamber 14 to provide support and protectionabout the primer flash hole 40. When contacted the coupling end 22interlocks with the substantially cylindrical coupling element 30,through the coupling element 30 that extends with a taper to a smallerdiameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28.

FIG. 8 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component 18 may be formed with coupling end 22formed on end 20. Coupling end 22 is shown as a female element, but mayalso be configured as a male element in alternate embodiments of theinvention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 is positionedfrom the flash hole aperture 41 and extends the length of the bottom ofthe primer recess and extends to at least a portion of the sidewall ofthe primer recess. The groove 35 may extend from the bottom of theprimer recess to the top surface terminating before the top surface 36.The groove 35 may be of any depth and may be of equal or varying depthalong its length or may be angled, arced, segmented (positive ornegative) or other variations over a portion, segments, or regions ofthe groove 35. In addition, the groove 35 may be textured to furthergrip the overmolding. The texture may be grooves, slots, squares,knurled, hatched, etched, indentions, or other known surface texturing.The texture may be of any depth, width or spacing being regular orirregular. The texturing may be combinations of textures and/or onlytextured in portions of the groove 35. The groove 35 receives thepolymer that is overmolded over the tip 44 and through the flash holeaperture 41 into the groove 35. The groove 35 extends away from theflash hole aperture 41 to allow the overmolding of the polymer into thegroove 35 and primer recess 38. The coupling end 22 extends the polymerthrough the primer flash hole 40 to form an aperture coating 42 whileretaining a passage from the top surface 36 through the bottom surface34 and into the powder chamber 14 to provide support and protectionabout the primer flash hole 40. When contacted the coupling end 22interlocks with the substantially cylindrical coupling element 30,through the coupling element 30 that extends with a taper to a smallerdiameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28.

FIG. 9 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case displaying ribs according to one embodiment ofthe present invention. One embodiment that reduces bellowing of theinsert includes a shortened insert and angled coupling element 30 insideof the insert. In addition, the raised portion of the polymer at theflash hole was removed, the internal polymer wall was lowered and angledto match the insert and the internal ribs were lengthened. Although FIG.9 shows one embodiment, this embodiment will apply equally to anyembodiment shown in the figures and/or known to the skilled artisan fromthis disclosure. For example, the polymeric cartridge case displayingribs may be used in conjunction with the inserts shown and described inFIGS. 3-8 and variations as described herein.

A portion of a cartridge suitable for use with high velocity rifles isshown manufactured with a polymer casing 12 showing a powder chamber 14.Polymer casing 12 has a substantially cylindrical opposite end 20. Thebullet-end component 18 may be formed with coupling end 22 formed on end20. Coupling end 22 is shown as a female element, but may also beconfigured as a male element in alternate embodiments of the invention.The middle body component (not shown) is connected to a substantiallycylindrical coupling element 30 of the substantially cylindrical insert32. Coupling element 30, as shown may be configured as a male element,however, all combinations of male and female configurations isacceptable for coupling elements 30 and coupling end 22 in alternateembodiments of the invention. Coupling end 22 fits about and engagescoupling element 30 of a substantially cylindrical insert 32. Thesubstantially cylindrical insert 32 includes a substantially cylindricalcoupling element 30 extending from a bottom surface 34 that is oppositea top surface 36. Located in the top surface 36 is a primer recess 38that extends toward the bottom surface 34. A primer flash hole 40 islocated in the primer flash hole 40 and extends through the bottomsurface 34 into the powder chamber 14. The coupling end 22 extends thepolymer through the primer flash hole 40 to form an aperture coating 42while retaining a passage from the top surface 36 through the bottomsurface 34 and into the powder chamber 14 to provide support andprotection about the primer flash hole 40. When contacted the couplingend 22 interlocks with the substantially cylindrical coupling element30, through the coupling element 30 that extends with a taper to asmaller diameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28. The substantially cylindrical opposite end 20 oranywhere within the powder chamber 14 may include one or more ribs 48 onthe surface. The number of ribs 48 will depend on the specificapplication and desire of the manufacture but may include 1, 2, 3, 4, 56, 7, 8, 9, 10, or more ribs. In the counter bore, the polymer washaving difficulty filling this area due to the fact that the polymerused has fillers in it, and needed to be reblended during molding. Oneembodiment includes six ribs 48 to create turbulence in the flow of thepolymer, thus allowing the material to fill the counter bore. Anotherembodiment of the instant invention is a shortened insert and angledcoupling element 30 inside of the insert. In addition, raised portionsof the polymer at the flash hole, lowered and angled the internalpolymer wall to match the insert and lengthened the internal ribs.

FIG. 10 depicts a side, cross-sectional view of a polymeric cartridgecase having a diffuser according to one embodiment of the presentinvention. The diffuser 50 is a device that is used to divert theaffects of the primer off of the polymer and directing it to the flashhole. The affects being the impact from igniting the primer as far aspressure and heat. Although FIG. 10 shows one embodiment, thisembodiment will apply equally to any embodiment shown in the figuresand/or known to the skilled artisan from this disclosure. For example,the polymeric cartridge case and diffuser may be used in conjunctionwith the inserts shown and described in FIGS. 3-9 and variations asdescribed herein. A cartridge 10 suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14 with projectile (not shown) inserted into the forward endopening 16. Polymer casing 12 has a substantially cylindrical open-endedpolymeric bullet-end 18 extending from forward end opening 16 rearwardto the opposite end 20. The bullet-end component 18 may be formed withcoupling end 22 formed on end 20. Coupling end 22 is shown as a femaleelement, but may also be configured as a male element in alternateembodiments of the invention. The forward end of bullet-end component 18has a shoulder 24 forming chamber neck 26.

The middle body component 28 is connected to a substantially cylindricalcoupling element 30 of the substantially cylindrical insert 32. Couplingelement 30, as shown may be configured as a male element, however, allcombinations of male and female configurations is acceptable forcoupling elements 30 and coupling end 22 in alternate embodiments of theinvention. Coupling end 22 of bullet-end component 18 fits about andengages coupling element 30 of a substantially cylindrical insert 32.The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A primer flash hole40 is located in the primer flash hole 40 and extends through the bottomsurface 34 into the powder chamber 14. The coupling end 22 extends thepolymer through the primer flash hole 40 to form an aperture coating 42while retaining a passage from the top surface 36 through the bottomsurface 34 and into the powder chamber 14 to provides support andprotection about the primer flash hole 40. When contacted the couplingend 22 interlocks with the substantially cylindrical coupling element30, through the coupling element 30 that extends with a taper to asmaller diameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28. The middle body component extends from a forward endopening 16 to coupling element 22. Located in the top surface 36 is aprimer recess 38 that extends toward the bottom surface 34 with adiffuser 50 positioned in the primer recess 38. The diffuser 50 includesa diffuser aperture 52 that aligns with the primer flash hole 40. Thediffuser 50 is a device that is used to divert the affects of the primer(not shown) off of the polymer. The affects being the impact fromigniting the primer as far as pressure and heat to divert the energy ofthe primer off of the polymer and directing it to the flash hole.

FIG. 11 depicts a side, cross-sectional view of a portion of thepolymeric cartridge case having a diffuser according to one embodimentof the present invention. Although FIG. 11 shows one embodiment, thisembodiment will apply equally to any embodiment shown in the figuresand/or known to the skilled artisan from this disclosure. For example,the polymeric cartridge case and diffuser may be used in conjunctionwith the inserts shown and described in FIGS. 3-9 and variations asdescribed herein. A portion of a cartridge suitable for use with highvelocity rifles is shown manufactured with a polymer casing 12 showing apowder chamber 14. Polymer casing 12 has a substantially cylindricalopposite end 20. The bullet-end component 18 may be formed with couplingend 22 formed on end 20. Coupling end 22 is shown as a female element,but may also be configured as a male element in alternate embodiments ofthe invention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A primer flash hole40 extends through the bottom surface 34 into the powder chamber 14. Thecoupling end 22 extends the polymer through the primer flash hole 40 toform an aperture coating 42 while retaining a passage from the topsurface 36 through the bottom surface 34 and into the powder chamber 14to provides support and protection about the primer flash hole 40. Whencontacted the coupling end 22 interlocks with the substantiallycylindrical coupling element 30, through the coupling element 30 thatextends with a taper to a smaller diameter at the tip 44 to form aphysical interlock between substantially cylindrical insert 32 andmiddle body component 28. Polymer casing 12 also has a substantiallycylindrical open-ended middle body component 28. Located in the topsurface 36 is a primer recess 38 that extends toward the bottom surface34 with a diffuser 50 positioned in the primer recess 38. The diffuser50 includes a diffuser aperture 52 and a diffuser aperture extension 54that aligns with the primer flash hole 40. The diffuser 50 is a devicethat is used to divert the affects of the primer (not shown) off of thepolymer. The affects being the impact from igniting the primer as far aspressure and heat to divert the energy of the primer off of the polymerand directing it to the flash hole. The diffuser 50 can be between 0.004to 0.010 inches in thickness and made from half hard brass. For example,the diffuser 50 can be between 0.005 inches thick for a 5.56 diffuser50. The OD of the diffuser for a 5.56 or 223 case is 0.173 and the ID is0.080. The diffuser could be made of any material that can withstand theenergy from the ignition of the primer. This would include steel,stainless, cooper, aluminum or even an engineered resin that wasinjection molded or stamped. The Diffuser can be produce in T shape bydrawing the material with a stamping and draw die. In the T Diffuser thecenter ring can be 0.005 to 0.010 tall and the OD is 0.090 and the ID0.080.

FIGS. 12-13 show a bottom view of the polymer casing. The substantiallycylindrical insert 32 is shown from below showing the top surface 36 andthe primer recess 38. The substantially cylindrical insert 32 has beenovermolded with the polymer mid-body (not shown). The flash holeaperture (not shown) is overmolded with an aperture coating 42 (i.e.,polymer overmolded) to form a primer flash hole 40. The groove (notshown) extends to the side wall (not shown) of the primer recess 38 toallow the bottom surface of the primer recess 38 to be overmolded. Thebottom surface of the primer recess 38 may include raised pads 39 a-39 dthat align to contact the primer (not shown) when inserted to allow theprimer (not shown) to operate. The overmolding flows through the flashhole aperture (not shown) to the groove (not shown) and around theraised pads 39 a-39 d. The number, size and position of the raised padsmay vary depending on the specific embodiment. For example, the raisedpads 39 a-39 c may be 3 pads (FIG. 13) or may be 4 pads 39 a-39 d (FIG.12) that align with the bottom of the primer (not shown) to providecontact and operation. The actual number and shape of the pads maynumber 2, 3, 4, 5, 6, 7, 8, 9 or more. The size and shape may be square,triangular, circular, trapezoidal and may have one or more curved sides.For example, the trapezoid may have curved walls to mirror the primerrecess 38 and the primer flash hole 40.

FIG. 14 depicts an elevated, cross-sectional view of a portion of thepolymeric cartridge case according to one embodiment of the presentinvention. A portion of a cartridge suitable for use with high velocityrifles is shown manufactured with a polymer casing 12 showing a powderchamber 14. Polymer casing 12 has a substantially cylindrical oppositeend 20. The bullet-end component (not shown) may be formed with couplingend 22 formed on end 20. Coupling end 22 is shown as a female element,but may also be configured as a male element in alternate embodiments ofthe invention. The middle body component (not shown) is connected to asubstantially cylindrical coupling element 30 of the substantiallycylindrical insert 32. Coupling element 30, as shown may be configuredas a male element, however, all combinations of male and femaleconfigurations is acceptable for coupling elements 30 and coupling end22 in alternate embodiments of the invention. Coupling end 22 fits aboutand engages coupling element 30 of a substantially cylindrical insert32. The substantially cylindrical insert 32 includes a substantiallycylindrical coupling element 30 extending from a bottom surface 34 thatis opposite a top surface 36. Located in the top surface 36 is a primerrecess 38 that extends toward the bottom surface 34. A flash holeaperture 41 is located in the primer recess 38 and extends through thebottom surface 34 into the powder chamber 14. The flash hole aperture 41is overmolded with an aperture coating 42 (i.e., polymer overmolded) toform a primer flash hole 40. A groove 35 is positioned around the flashhole aperture 41 in the primer recess 38. The groove 35 may be of anydepth in the primer recess 38 and may extend away from the flash holeaperture 41 toward the primer recess wall 37 of the primer recess 38. Inaddition, the groove 35 may be textured to further grip the overmolding.The texture may be grooves, slots, squares, knurled, hatched, etched orother known surface texturing. The texture may be of any depth, width orspacing being regular or irregular. The texturing may be combinations oftextures and/or textured in portions of the groove 35. The groove 35receives the polymer that is overmolded over the tip 44 and through theflash hole aperture 41 into the groove 35. The groove 35 extends awayfrom the flash hole aperture 41 to allow the overmolding of the polymerinto the groove 35 and primer recess 38. The bottom surface 34 of theprimer recess 38 may include raised pad 39 that align to contact theprimer (not shown) when inserted into the primer recess 38 to allow theprimer (not shown) to operate. The overmolding flows through the flashhole aperture 41 to the groove 35 and around the raised pad 39. Thenumber, size and position of the raised pads may vary depending on thespecific embodiment. The actual number and shape of the pads may number2, 3, 4, 5, 6, 7, 8, 9 or more. The size and shape may be square,triangular, circular, trapezoidal and may have one or more curved sides.For example, the trapezoid may have curved walls to mirror the primerrecess wall 37 and the primer flash hole 40. The coupling end 22 extendsthe polymer through the primer flash hole 40 to form an aperture coating42 while retaining a passage from the top surface 36 through the bottomsurface 34 and into the powder chamber 14 to provide support andprotection about the primer flash hole 40. When contacted the couplingend 22 interlocks with the substantially cylindrical coupling element30, through the coupling element 30 that extends with a taper to asmaller diameter at the tip 44 to form a physical interlock betweensubstantially cylindrical insert 32 and middle body component 28.Polymer casing 12 also has a substantially cylindrical open-ended middlebody component 28.

The polymeric and composite casing components may be injection molded.Polymeric materials for the bullet-end and middle body components musthave propellant compatibility and resistance to gun cleaning solventsand grease, as well as resistance to chemical, biological andradiological agents. The polymeric materials must have a temperatureresistance higher than the cook-off temperature of the propellant,typically about 320° F. The polymeric materials must haveelongation-to-break values that to resist deformation under interiorballistic pressure as high as 60,000 psi in all environments(temperatures from about −65 to about 320° F. and humidity from 0 to100% RH). According to one embodiment, the middle body component iseither molded onto or snap-fit to the casing head-end component afterwhich the bullet-end component is snap-fit or interference fit to themiddle body component. The components may be formed from high-strengthpolymer, composite or ceramic.

Examples of suitable high strength polymers include composite polymermaterial including a tungsten metal powder, nylon 6/6, nylon 6, andglass fibers; and a specific gravity in a range of 3-10. The tungstenmetal powder may be 50%-96% of a weight of the bullet body. The polymermaterial also includes about 0.5-15%, preferably about 1-12%, and mostpreferably about 2-9% by weight, of nylon 6/6, about 0.5-15%, preferablyabout 1-12%, and most preferably about 2-9% by weight, of nylon 6, andabout 0.5-15%, preferably about 1-12%, and most preferably about 2-9% byweight, of glass fibers. It is most suitable that each of theseingredients be included in amounts less than 10% by weight. Thecartridge casing body may be made of a modified ZYTEL resin, availablefrom E.I. DuPont De Nemours Co., a modified 612 nylon resin, modified toincrease elastic response.

Examples of suitable polymers include polyurethane prepolymer,cellulose, fluoro-polymer, ethylene inter-polymer alloy elastomer,ethylene vinyl acetate, nylon, polyether imide, polyester elastomer,polyester sulfone, polyphenyl amide, polypropylene, polyvinylidenefluoride or thermoset polyurea elastomer, acrylics, homopolymers,acetates, copolymers, acrylonitrile-butadinen-styrene, thermoplasticfluoro polymers, inomers, polyamides, polyamide-imides, polyacrylates,polyatherketones, polyaryl-sulfones, polybenzimidazoles, polycarbonates,polybutylene, terephthalates, polyether imides, polyether sulfones,thermoplastic polyimides, thermoplastic polyurethanes, polyphenylenesulfides, polyethylene, polypropylene, polysulfones, polyvinylchlorides,styrene acrylonitriles, polystyrenes, polyphenylene, ether blends,styrene maleic anhydrides, polycarbonates, allyls, aminos, cyanates,epoxies, phenolics, unsaturated polyesters, bismaleimides,polyurethanes, silicones, vinylesters, or urethane hybrids. Examples ofsuitable polymers also include aliphatic or aromatic polyamide,polyeitherimide, polysulfone, polyphenylsulfone, poly-phenylene oxide,liquid crystalline polymer and polyketone. Examples of suitablecomposites include polymers such as polyphenylsulfone reinforced withbetween about 30 and about 70 wt %, and preferably up to about 65 wt %of one or more reinforcing materials selected from glass fiber, ceramicfiber, carbon fiber, mineral fillers, organo nanoclay, or carbonnanotube. Preferred reinforcing materials, such as choppedsurface-treated E-glass fibers provide flow characteristics at theabove-described loadings comparable to unfilled polymers to provide adesirable combination of strength and flow characteristics that permitthe molding of head-end components. Composite components can be formedby machining or injection molding. Finally, the cartridge case mustretain sufficient joint strength at cook-off temperatures. Morespecifically, polymers suitable for molding of the projectile-endcomponent have one or more of the following properties: Yield or tensilestrength at −65° F.>10,000 psi Elongation-to-break at −65° F.>15% Yieldor tensile strength at 73° F.>8,000 psi Elongation-to-break at 73°F.>50% Yield or tensile strength at 320° F.>4,000 psiElongation-to-break at 320° F.>80%. Polymers suitable for molding of themiddle-body component have one or more of the following properties:Yield or tensile strength at −65° F.>10,000 psi Yield or tensilestrength at 73° F.>8,000 psi Yield or tensile strength at 320° F.>4,000psi.

Commercially available polymers suitable for use in the presentinvention thus include polyphenylsulfones; copolymers ofpolyphenylsulfones with polyether-sulfones or polysulfones; copolymersand blends of polyphenylsulfones with polysiloxanes;poly(etherimide-siloxane); copolymers and blends of polyetherimides andpolysiloxanes, and blends of polyetherimides andpoly(etherimide-siloxane) copolymers; and the like. Particularlypreferred are polyphenylsulfones and their copolymers with poly-sulfonesor polysiloxane that have high tensile strength and elongation-to-breakto sustain the deformation under high interior ballistic pressure. Suchpolymers are commercially available, for example, RADEL R5800polyphenylesulfone from Solvay Advanced Polymers. The polymer can beformulated with up to about 10 wt % of one or more additives selectedfrom internal mold release agents, heat stabilizers, anti-static agents,colorants, impact modifiers and UV stabilizers.

The polymers of the present invention can also be used for conventionaltwo-piece metal-plastic hybrid cartridge case designs and conventionalshotgun shell designs. One example of such a design is an ammunitioncartridge with a one-piece substantially cylindrical polymeric cartridgecasing body with an open projectile-end and an end opposing theprojectile-end with a male or female coupling element; and a cylindricalmetal cartridge casing head-end component with an essentially closedbase end with a primer hole opposite an open end having a couplingelement that is a mate for the coupling element on the opposing end ofthe polymeric cartridge casing body joining the open end of the head-endcomponent to the opposing end of the polymeric cartridge casing body.The high polymer ductility permits the casing to resist breakage.

One embodiment includes a 2 cavity prototype mold having an upperportion and a base portion for a 5.56 case having a metal insertover-molded with a Nylon 6 (polymer) based material. In this embodimentthe polymer in the base includes a lip or flange to extract the casefrom the weapon. One 2-cavity prototype mold to produce the upperportion of the 5.56 case can be made using a stripper plate tool usingan Osco hot spur and two subgates per cavity. Another embodimentincludes a subsonic version, the difference from the standard and thesubsonic version is the walls are thicker thus requiring less powder.This will decrease the velocity of the bullet thus creating a subsonicround.

The extracting inserts is used to give the polymer case a tough enoughridge and groove for the weapons extractor to grab and pull the case outthe chamber of the gun. The extracting insert is made of 17-4 ss that ishardened to 42-45rc. The insert may be made of aluminum, brass, cooper,steel or even an engineered resin with enough tensile strength.

The insert is over molded in an injection molded process using a nanoclay particle filled Nylon material. The inserts can be machined orstamped. In addition, an engineered resin able to withstand the demandon the insert allows injection molded and/or even transfer molded.

One of ordinary skill in the art will know that many propellant typesand weights can be used to prepare workable ammunition and that suchloads may be determined by a careful trial including initial lowquantity loading of a given propellant and the well known stepwiseincreasing of a given propellant loading until a maximum acceptable loadis achieved. Extreme care and caution is advised in evaluating newloads. The propellants available have various burn rates and must becarefully chosen so that a safe load is devised.

The description of the preferred embodiments should be taken asillustrating, rather than as limiting, the present invention as definedby the claims. As will be readily appreciated, numerous combinations ofthe features set forth above can be utilized without departing from thepresent invention as set forth in the claims. Such variations are notregarded as a departure from the spirit and scope of the invention, andall such modifications are intended to be included within the scope ofthe following claims.

It is contemplated that any embodiment discussed in this specificationcan be implemented with respect to any method, kit, reagent, orcomposition of the invention, and vice versa. Furthermore, compositionsof the invention can be used to achieve methods of the invention.

It will be understood that particular embodiments described herein areshown by way of illustration and not as limitations of the invention.The principal features of this invention can be employed in variousembodiments without departing from the scope of the invention. Thoseskilled in the art will recognize, or be able to ascertain using no morethan routine experimentation, numerous equivalents to the specificprocedures described herein. Such equivalents are considered to bewithin the scope of this invention and are covered by the claims.

All publications and patent applications mentioned in the specificationare indicative of the level of skill of those skilled in the art towhich this invention pertains. All publications and patent applicationsare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

The use of the word “a” or “an” when used in conjunction with the term“comprising” in the claims and/or the specification may mean “one,” butit is also consistent with the meaning of “one or more,” “at least one,”and “one or more than one.” The use of the term “or” in the claims isused to mean “and/or” unless explicitly indicated to refer toalternatives only or the alternatives are mutually exclusive, althoughthe disclosure supports a definition that refers to only alternativesand “and/or.” Throughout this application, the term “about” is used toindicate that a value includes the inherent variation of error for thedevice, the method being employed to determine the value, or thevariation that exists among the study subjects.

As used in this specification and claim(s), the words “comprising” (andany form of comprising, such as “comprise” and “comprises”), “having”(and any form of having, such as “have” and “has”), “including” (and anyform of including, such as “includes” and “include”) or “containing”(and any form of containing, such as “contains” and “contain”) areinclusive or open-ended and do not exclude additional, unrecitedelements or method steps.

The term “or combinations thereof” as used herein refers to allpermutations and combinations of the listed items preceding the term.For example, “A, B, C, or combinations thereof” is intended to includeat least one of: A, B, C, AB, AC, BC, or ABC, and if order is importantin a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB.Continuing with this example, expressly included are combinations thatcontain repeats of one or more item or term, such as BB, AAA, MB, BBC,AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan willunderstand that typically there is no limit on the number of items orterms in any combination, unless otherwise apparent from the context.

All of the compositions and/or methods disclosed and claimed herein canbe made and executed without undue experimentation in light of thepresent disclosure. While the compositions and methods of this inventionhave been described in terms of preferred embodiments, it will beapparent to those of skill in the art that variations may be applied tothe compositions and/or methods and in the steps or in the sequence ofsteps of the method described herein without departing from the concept,spirit and scope of the invention. All such similar substitutes andmodifications apparent to those skilled in the art are deemed to bewithin the spirit, scope and concept of the invention as defined by theappended claims.

What is claimed is:
 1. A primer insert for use in a polymeric ammunition cartridge comprising: a top surface opposite a bottom surface and a extraction flange that extends circumferentially about an outer edge of the top surface; a coupling element that extends from the bottom surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; a primer recess in the top surface that extends toward the bottom surface, wherein the primer recess comprises a recess bottom and a circular recess side wall; a primer flash aperture through the recess bottom that extends through the bottom surface, wherein the primer flash aperture is adapted to receive a polymer overmolding to form a flash hole; and a groove in the primer recess positioned around the primer flash aperture adapted to receive a polymer overmolding, wherein the groove extends at least partially over the bottom surface and the circular recess side wall and the groove is adapted to receive polymer through the primer flash aperture and over the bottom surface and the circular recess side wall.
 2. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 95-100 percent the distance from the recess bottom to the top surface.
 3. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 95 percent the distance from the recess bottom to the top surface.
 4. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 96 percent the distance from the recess bottom to the top surface.
 5. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 97 percent the distance from the recess bottom to the top surface.
 6. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 98 percent the distance from the recess bottom to the top surface.
 7. The primer insert of claim 1, wherein the groove extends up the circular recess side wall about 99 percent the distance from the recess bottom to the top surface.
 8. The primer insert of claim 1, wherein the groove extends to about the circular recess side wall.
 9. The primer insert of claim 1, wherein the coupling element comprises an inner surface adapted to receive a polymer overmolding and an outer surface adapted to receive a polymer overmolding.
 10. The primer insert of claim 1, further comprising an outer molding groove that extends circumferentially about an outer edge of the top surface.
 11. The primer insert of claim 1, wherein the primer insert has a caliber selected from .223, .243, .25-06, .270, .300, .308, .338, .30-30, .30-06, .45-70 or 0.50-90, 50 caliber, 45 caliber, 380 caliber or 38 caliber, 5.56 mm, 6 mm, 7 mm, 7.62 mm, 8 mm, 9 mm, 10 mm, or 12.7 mm.
 12. The primer insert of claim 1, wherein the primer insert is a 5.56 mm, 7.62 mm, .223, 308, 338, 12.7 mm, and .50 caliber primer insert.
 13. The primer insert of claim 1, wherein the primer insert comprises a metal, an alloy, a polymer or a ceramic alloy.
 14. The primer insert of claim 1, wherein the primer insert comprises steel, nickel, chromium, copper, carbon, iron, stainless steel or brass.
 15. The primer insert of claim 1, wherein the primer insert comprises a 102, 174, 201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or 601-665 grade stainless steel.
 16. The primer insert of claim 1, wherein the primer insert comprises a Ti₆Al₄V.
 17. The primer insert of claim 1, wherein the primer insert comprises a groove texture. 